1. Field of the Invention
The present invention relates to a time correction apparatus and an image forming device having the time correction apparatus in which the time correction apparatus determines whether the present time is within a summer time period, and performs time correction during the summer time.
2. Description of the Related Art
It is known that the summer time system is carried out in some countries and the standard time is set forward by one or two hours during the summer time. In connection with this, a conventional time correction apparatus which corrects the present time during the summer time is proposed for communication devices, such as facsimile devices, in which the time indication is performed or the automatic communication by a timer control is carried out.
Japanese Laid-Open Patent Application No. 2001-042072 discloses a time adjusting device and method which makes it possible to adjust time in the summer time period or in the other time period, without the need for the user to perform complicated operations, even if a summer time system will be provided in the future in the areas where the summer time system is not carried out at present.
Moreover, Japanese Laid-Open Patent Application No. 2001-318174 discloses an image forming device which causes the setting time of the timer function to be automatically corrected, when a change of the standard time zone and the summer time zone occurs, based on the time difference between the two time zones.
The amount of time correction in the summer time period is fixed to one hour in the conventional time correction apparatus, and if the summer time system in which the time correction requiring the amount of time correction other than one hour is adopted in the future, it is difficult for the conventional time correction apparatus to properly correct the present time during the summer time. Moreover, it is necessary to perform the complicated operations to modify the software provided in the image forming device, in order to properly correct the present time during the summer time.
In the case of the time correction apparatus disclosed in Japanese Laid-Open Patent Applications No. 2001-042072 and No. 2001-318174, the amount of time correction in the summer time period is fixed to one hour, and the present time is compared with the summer time start date/time and the summer time end date/time of the year concerned only. Namely, the determination as to whether the present time is within the summer time period is performed only for the year concerned.
Moreover, in the case of the above-mentioned time correction apparatus, it is determined whether the present time is within the summer time period of the year concerned only. When the continuous operation of the image forming device over two or more consecutive years is demanded, a faulty time correction may occur.
In order to avoid the problem and allow the continuous operation of the image forming device over two or more consecutive years, the time change should be monitored over the two or more consecutive years and the processing to update the summer time start date/time and the summer time end date/time year by year should be performed.
In the communication devices, such as facsimile devices, in which the time indication and the automatic communication by the timer control are performed, the time correction processing is performed frequently. However, in such cases, it is desired that the increasing of the CPU load due to the time correction processing be prevented.